Re: Atomic wallet. Bitcoin sent to a Dogecoin address, how was that possible?
Essentially, Atomic seems to have simply converted the DOGE address from Base58Check to HEX, then stripped off the DOGE "address prefix" (0x1e == "D") and the "checksum bytes", added the BTC address prefix (0x00 == "1") and then recalculated and appended the checksum and then converted from HEX back to Base58Check to end up with a BTC address... 
Lol
This is very crazy.
This is very arbitrary. This should never be done in a wallet, or any kind of software that deals with other people' money.
Atomic wallet is not capable of handling other people' funds.